What is a turbocharger and how does a turbocharger work?
Cummins Turbo Technologies gives you a
comprehensive guide to turbocharging....
The purpose of a turbocharger is to compress the air flowing into the diesel engine, this lets the engine squeeze more air into a cylinder and more air means that more fuel can be added. The engine burns air and fuel to create mechanical power, the more air and fuel it can burn the more powerful it is.
terms, a turbocharger comprises
of a turbine and a compressor connected
by a common shaft supported on
a bearing system. The turbocharger
converts waste energy from an engine's
exhaust gases into compressed
air, which it pushes into the engine.
This allows the engine to burn more fuel producing more power and improve
the overall efficiency of the combustion
the opposite of turbines. They consist of two sections,
the impeller or compressor
wheel and the compressor
housing. The compressor
wheel is connected to the turbine by
a forged steel shaft. As the compressor
wheel spins, air
is drawn in and is
compressed as the blades spin at a high velocity.
The housing is designed to convert the high velocity,
low pressure air stream, into a high pressure low
velocity air stream, through a process called diffusion.
In order to achieve this boost, the turbocharger uses the exhaust flow from the engine to spin a turbine, which in turn spins an air pump. The turbine in the turbocharger spins at speeds of up to 200 krpm rotations per minute (rpm) that is about 30 times faster than most car engines can go. Since it is connected to the exhaust, the temperatures in the turbine are also very high. Air enters the compressor at a temperature equivalent to atmosphere. However, as compression causes the temperature of the air to rise it leaves the compressor cover at temperatures up to 200 degrees celcius.
Bearings are a free-floating rotational
type. To perform correctly, the journal bearings
float between two films of oil. The bearing clearances are very small,
less than the width of a human hair. Dirty oil
or blockages in the oil supply holes can cause
serious damage to the turbocharger.